Process of preparing aliphatic fluorine compounds



Pee -mi Feb. 1, ice

PRQCESS OF PREPARING 1 FLUORENE COIVWOS om dchcrcr, ort-on-the--Hochnt,

Ge tie in designer to I. G. Farhenindustrie Akaelischalt,ort-on-the-Main, Ger- No wing. Application November 26, 1935, Serial No.51,711. In Germany November 29,

3 Claims. (01. 260-653) The present invention relates to a process 0preparing aliphatic fluorine compounds.

Aliphatic fluorine compounds have hitherto been made by causing thecorresponding chlorine compounds to react with antimony trifluoride orhydrogenfluoride in the presence of antimony pentafluoride, pentavalentantimony reacting as a catalyst. Furthermore antimony trifiuoride hasbeen used in the presence of bromine, pentavalent antimony beingintermediately produced. This, procedure has the drawback that besidesthe real. reaction, namely the substitution of fluorine for chlorine, achlorination or a bromination also occurs when compounds containinghydrogen are used. According to this method'it is, for instance, almostimpossible to prepare compounds such as methylfluoroform or ethylidenefluoride, since the hydrogen is in part exchanged for chlorine. i

Now I have found that aliphatic hydrocarbon chlorides with at least 2carbon atoms, the chlorine atoms of which are, attached only to onecarbon atom, for instance, methylchloroform or ethylidene chloride canalso be fluorlnated ata raised temperature with the aid of afluorinating agent, but without the addition of pentavalent antimony. Asfluorin'ating agent there is invention, but they are not intended tolimit it thereto:

-(1) In an iron vessel resistant topressure, methyl-chloroform is mixedwith SbF: or HF.

this operation the pressure very soon rises. If as fluorinating agenthydrogen fluoride is used, hydrochloric acid is then discharged by meansof a valve. After 1 to 2 hours the reaction is complete. According tothe quantity of the 1111- orinating agent used there is obtained(JUMP-CH3. CClFa-CH: or CF:-CH: (2) Under the same conditions asdescribed in Example .1 there is obtained from ethylidene 15 chloride,according to the experimental conditions', CHClF-C'Hs or CHFaCHs.

I claim:

1. In the process oi. preparing aliphatic fluorine compounds the stepwhich consists in heat- .ing in a closed vessel practically anhydroushydrogen fluoride and an aliphatic hydrocarbon with two carbon atomscontaining at least two chlorine atoms at only one carbon atom.

2. In the process of preparing aliphatic fluorine compounds the stepwhich consists in heatingin a closed vessel practically anhydroushydrogen florlde and methylchloroform at a temperature of about 150 C.

3. In the .of preparing aliphatic fluorine compounds the step whichconsists in heat- 1 ing ina closed vessel practically anhydrous hydrogenfluoride and 'ethylidene chloride at a temperatureoi about 150 C.

The vessel is heated to about 150 0. During 5

